package com.jun.plugin.poi.test.excel.reader.usermodel;

import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;
import java.util.regex.Pattern;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.util.LocaleUtil;
/**
 * Contains methods for dealing with Excel dates.
 * change form {@link org.apache.poi.ss.usermodel.DateUtil};
 */
public class ExcelDateUtil {

    protected ExcelDateUtil() {
        // no instances of this class
    }

    public static final int SECONDS_PER_MINUTE = 60;
    public static final int MINUTES_PER_HOUR = 60;
    public static final int HOURS_PER_DAY = 24;
    public static final int SECONDS_PER_DAY = (HOURS_PER_DAY * MINUTES_PER_HOUR * SECONDS_PER_MINUTE);

    private static final int    BAD_DATE         = -1;   // used to specify that date is invalid
    public static final long   DAY_MILLISECONDS = SECONDS_PER_DAY * 1000L;

    private static final Pattern TIME_SEPARATOR_PATTERN = Pattern.compile(":");

    /**
     * The following patterns are used in {@link #isADateFormat(int, String)}
     */
    private static final Pattern date_ptrn1 = Pattern.compile("^\\[\\$\\-.*?\\]");
    private static final Pattern date_ptrn2 = Pattern.compile("^\\[[a-zA-Z]+\\]");
    private static final Pattern date_ptrn3 = Pattern.compile("^\\[[DBNum]+\\d{1}\\]");
    private static final Pattern date_chinese = Pattern.compile("[年月日时分秒]|(上午)|(下午)");
    private static final Pattern date_ptrn3a = Pattern.compile("[yYmMdDhHsS]");
    private static final Pattern date_ptrn3b = Pattern.compile("^[\\[\\]yYmMdDhHsS\\-T/,. :\"\\\\]+0*[ampAMP/]*$");
    //  elapsed time patterns: [h],[m] and [s]
    private static final Pattern date_ptrn4 = Pattern.compile("^\\[([hH]+|[mM]+|[sS]+)\\]");

    /**
     * Given a Date, converts it into a double representing its internal Excel representation,
     *   which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds.
     *
     * @return Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
     * @param  date the Date
     */
    public static double getExcelDate(Date date) {
        return getExcelDate(date, false);
    }
    /**
     * Given a Date, converts it into a double representing its internal Excel representation,
     *   which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds.
     *
     * @return Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
     * @param date the Date
     * @param use1904windowing Should 1900 or 1904 date windowing be used?
     */
    public static double getExcelDate(Date date, boolean use1904windowing) {
        Calendar calStart = LocaleUtil.getLocaleCalendar();
        calStart.setTime(date);   // If date includes hours, minutes, and seconds, set them to 0
        return internalGetExcelDate(calStart, use1904windowing);
    }
    /**
     * Given a Date in the form of a Calendar, converts it into a double
     *  representing its internal Excel representation, which is the
     *  number of days since 1/1/1900. Fractional days represent hours,
     *  minutes, and seconds.
     *
     * @return Excel representation of Date (-1 if error - test for error by checking for less than 0.1)
     * @param date the Calendar holding the date to convert
     * @param use1904windowing Should 1900 or 1904 date windowing be used?
     */
    public static double getExcelDate(Calendar date, boolean use1904windowing) {
        // Don't alter the supplied Calendar as we do our work
        return internalGetExcelDate( (Calendar)date.clone(), use1904windowing );
    }
    private static double internalGetExcelDate(Calendar date, boolean use1904windowing) {
        if ((!use1904windowing && date.get(Calendar.YEAR) < 1900) ||
            (use1904windowing && date.get(Calendar.YEAR) < 1904))
        {
            return BAD_DATE;
        }
        // Because of daylight time saving we cannot use
        //     date.getTime() - calStart.getTimeInMillis()
        // as the difference in milliseconds between 00:00 and 04:00
        // can be 3, 4 or 5 hours but Excel expects it to always
        // be 4 hours.
        // E.g. 2004-03-28 04:00 CEST - 2004-03-28 00:00 CET is 3 hours
        // and 2004-10-31 04:00 CET - 2004-10-31 00:00 CEST is 5 hours
        double fraction = (((date.get(Calendar.HOUR_OF_DAY) * 60
                             + date.get(Calendar.MINUTE)
                            ) * 60 + date.get(Calendar.SECOND)
                           ) * 1000 + date.get(Calendar.MILLISECOND)
                          ) / ( double ) DAY_MILLISECONDS;
        Calendar calStart = dayStart(date);

        double value = fraction + absoluteDay(calStart, use1904windowing);

        if (!use1904windowing && value >= 60) {
            value++;
        } else if (use1904windowing) {
            value--;
        }

        return value;
    }

    /**
     *  Given an Excel date with using 1900 date windowing, and
     *  converts it to a java.util.Date.
     *  
     *  Excel Dates and Times are stored without any timezone 
     *  information. If you know (through other means) that your file 
     *  uses a different TimeZone to the system default, you can use
     *  this version of the getJavaDate() method to handle it.
     *   
     *  @param date  The Excel date.
     *  @param tz The TimeZone to evaluate the date in
     *  @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Date getJavaDate(double date, TimeZone tz) {
       return getJavaDate(date, false, tz, false);
    }
    /**
     *  Given an Excel date with using 1900 date windowing, and
     *   converts it to a java.util.Date.
     *
     *  NOTE: If the default <code>TimeZone</code> in Java uses Daylight
     *  Saving Time then the conversion back to an Excel date may not give
     *  the same value, that is the comparison
     *  <CODE>excelDate == getExcelDate(getJavaDate(excelDate,false))</CODE>
     *  is not always true. For example if default timezone is
     *  <code>Europe/Copenhagen</code>, on 2004-03-28 the minute after
     *  01:59 CET is 03:00 CEST, if the excel date represents a time between
     *  02:00 and 03:00 then it is converted to past 03:00 summer time
     *
     *  @param date  The Excel date.
     *  @return Java representation of the date, or null if date is not a valid Excel date
     *  @see java.util.TimeZone
     */
    public static Date getJavaDate(double date) {
        return getJavaDate(date, false, null, false);
    }

    /**
     *  Given an Excel date with either 1900 or 1904 date windowing,
     *  converts it to a java.util.Date.
     *  
     *  Excel Dates and Times are stored without any timezone 
     *  information. If you know (through other means) that your file 
     *  uses a different TimeZone to the system default, you can use
     *  this version of the getJavaDate() method to handle it.
     *   
     *  @param date  The Excel date.
     *  @param tz The TimeZone to evaluate the date in
     *  @param use1904windowing  true if date uses 1904 windowing,
     *   or false if using 1900 date windowing.
     *  @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Date getJavaDate(double date, boolean use1904windowing, TimeZone tz) {
        return getJavaDate(date, use1904windowing, tz, false);
    }
    
    /**
     *  Given an Excel date with either 1900 or 1904 date windowing,
     *  converts it to a java.util.Date.
     *  
     *  Excel Dates and Times are stored without any timezone 
     *  information. If you know (through other means) that your file 
     *  uses a different TimeZone to the system default, you can use
     *  this version of the getJavaDate() method to handle it.
     *   
     *  @param date  The Excel date.
     *  @param tz The TimeZone to evaluate the date in
     *  @param use1904windowing  true if date uses 1904 windowing,
     *   or false if using 1900 date windowing.
     *  @param roundSeconds round to closest second
     *  @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Date getJavaDate(double date, boolean use1904windowing, TimeZone tz, boolean roundSeconds) {
        Calendar calendar = getJavaCalendar(date, use1904windowing, tz, roundSeconds);
        return calendar == null ? null : calendar.getTime();
    }
    
    /**
     *  Given an Excel date with either 1900 or 1904 date windowing,
     *  converts it to a java.util.Date.
     *
     *  NOTE: If the default <code>TimeZone</code> in Java uses Daylight
     *  Saving Time then the conversion back to an Excel date may not give
     *  the same value, that is the comparison
     *  <CODE>excelDate == getExcelDate(getJavaDate(excelDate,false))</CODE>
     *  is not always true. For example if default timezone is
     *  <code>Europe/Copenhagen</code>, on 2004-03-28 the minute after
     *  01:59 CET is 03:00 CEST, if the excel date represents a time between
     *  02:00 and 03:00 then it is converted to past 03:00 summer time
     *
     *  @param date  The Excel date.
     *  @param use1904windowing  true if date uses 1904 windowing,
     *   or false if using 1900 date windowing.
     *  @return Java representation of the date, or null if date is not a valid Excel date
     *  @see java.util.TimeZone
     */
    public static Date getJavaDate(double date, boolean use1904windowing) {
        return getJavaDate(date, use1904windowing, null, false);
    }

    public static void setCalendar(Calendar calendar, int wholeDays,
            int millisecondsInDay, boolean use1904windowing, boolean roundSeconds) {
        int startYear = 1900;
        int dayAdjust = -1; // Excel thinks 2/29/1900 is a valid date, which it isn't
        if (use1904windowing) {
            startYear = 1904;
            dayAdjust = 1; // 1904 date windowing uses 1/2/1904 as the first day
        }
        else if (wholeDays < 61) {
            // Date is prior to 3/1/1900, so adjust because Excel thinks 2/29/1900 exists
            // If Excel date == 2/29/1900, will become 3/1/1900 in Java representation
            dayAdjust = 0;
        }
        calendar.set(startYear,0, wholeDays + dayAdjust, 0, 0, 0);
        calendar.set(Calendar.MILLISECOND, millisecondsInDay);
        if (calendar.get(Calendar.MILLISECOND) == 0) {
            calendar.clear(Calendar.MILLISECOND);
        }
        if (roundSeconds) {
            calendar.add(Calendar.MILLISECOND, 500);
            calendar.clear(Calendar.MILLISECOND);
        }
    }


    /**
     * Get EXCEL date as Java Calendar (with default time zone).
     * This is like {@link #getJavaDate(double)} but returns a Calendar object.
     *  @param date  The Excel date.
     *  @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Calendar getJavaCalendar(double date) {
        return getJavaCalendar(date, false, (TimeZone)null, false);
    }

    /**
     * Get EXCEL date as Java Calendar (with default time zone).
     * This is like {@link #getJavaDate(double, boolean)} but returns a Calendar object.
     *  @param date  The Excel date.
     *  @param use1904windowing  true if date uses 1904 windowing,
     *   or false if using 1900 date windowing.
     *  @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Calendar getJavaCalendar(double date, boolean use1904windowing) {
        return getJavaCalendar(date, use1904windowing, (TimeZone)null, false);
    }

    /**
     * Get EXCEL date as Java Calendar with UTC time zone.
     * This is similar to {@link #getJavaDate(double, boolean)} but returns a
     * Calendar object that has UTC as time zone, so no daylight saving hassle.
     * @param date  The Excel date.
     * @param use1904windowing  true if date uses 1904 windowing,
     *  or false if using 1900 date windowing.
     * @return Java representation of the date in UTC, or null if date is not a valid Excel date
     */
    public static Calendar getJavaCalendarUTC(double date, boolean use1904windowing) {
    	return getJavaCalendar(date, use1904windowing, LocaleUtil.TIMEZONE_UTC, false);
    }


    /**
     * Get EXCEL date as Java Calendar with given time zone.
     * @param date  The Excel date.
     * @param use1904windowing  true if date uses 1904 windowing,
     *  or false if using 1900 date windowing.
     * @param timeZone The TimeZone to evaluate the date in
     * @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Calendar getJavaCalendar(double date, boolean use1904windowing, TimeZone timeZone) {
        return getJavaCalendar(date, use1904windowing, timeZone, false);
    }
        
    /**
     * Get EXCEL date as Java Calendar with given time zone.
     * @param date  The Excel date.
     * @param use1904windowing  true if date uses 1904 windowing,
     *  or false if using 1900 date windowing.
     * @param timeZone The TimeZone to evaluate the date in
     * @param roundSeconds round to closest second
     * @return Java representation of the date, or null if date is not a valid Excel date
     */
    public static Calendar getJavaCalendar(double date, boolean use1904windowing, TimeZone timeZone, boolean roundSeconds) {
        if (!isValidExcelDate(date)) {
            return null;
        }
        int wholeDays = (int)Math.floor(date);
        int millisecondsInDay = (int)((date - wholeDays) * DAY_MILLISECONDS + 0.5);
        Calendar calendar;
        if (timeZone != null) {
            calendar = LocaleUtil.getLocaleCalendar(timeZone);
        } else {
            calendar = LocaleUtil.getLocaleCalendar(); // using default time-zone
        }
        setCalendar(calendar, wholeDays, millisecondsInDay, use1904windowing, roundSeconds);
        return calendar;
    }

    // variables for performance optimization:
    // avoid re-checking DataUtil.isADateFormat(int, String) if a given format
    // string represents a date format if the same string is passed multiple times.
    // see https://issues.apache.org/bugzilla/show_bug.cgi?id=55611
    private static ThreadLocal<Integer> lastFormatIndex = new ThreadLocal<Integer>() {
        protected Integer initialValue() {
            return -1;
        }
    };
    private static ThreadLocal<String> lastFormatString = new ThreadLocal<String>();
    private static ThreadLocal<Boolean> lastCachedResult = new ThreadLocal<Boolean>();
    
    private static boolean isCached(String formatString, int formatIndex) {
        String cachedFormatString = lastFormatString.get();
        return cachedFormatString != null && formatIndex == lastFormatIndex.get()
                && formatString.equals(cachedFormatString);
    }

    private static void cache(String formatString, int formatIndex, boolean cached) {
        lastFormatIndex.set(formatIndex);
        lastFormatString.set(formatString);
        lastCachedResult.set(Boolean.valueOf(cached));
    }

    /**
     * Given a format ID and its format String, will check to see if the
     *  format represents a date format or not.
     * Firstly, it will check to see if the format ID corresponds to an
     *  internal excel date format (eg most US date formats)
     * If not, it will check to see if the format string only contains
     *  date formatting characters (ymd-/), which covers most
     *  non US date formats.
     *
     * @param formatIndex The index of the format, eg from ExtendedFormatRecord.getFormatIndex
     * @param formatString The format string, eg from FormatRecord.getFormatString
     * @see #isInternalDateFormat(int)
     */

    public static boolean isADateFormat(int formatIndex, String formatString) {
        // First up, is this an internal date format?
        if(isInternalDateFormat(formatIndex)) {
            cache(formatString, formatIndex, true);
            return true;
        }

        // If we didn't get a real string, don't even cache it as we can always find this out quickly
        if(formatString == null || formatString.length() == 0) {
            return false;
        }

        // check the cache first
        if (isCached(formatString, formatIndex)) {
            return lastCachedResult.get();
        }

        String fs = formatString;
        /*if (false) {
            // Normalize the format string. The code below is equivalent
            // to the following consecutive regexp replacements:

             // Translate \- into just -, before matching
             fs = fs.replaceAll("\\\\-","-");
             // And \, into ,
             fs = fs.replaceAll("\\\\,",",");
             // And \. into .
             fs = fs.replaceAll("\\\\\\.",".");
             // And '\ ' into ' '
             fs = fs.replaceAll("\\\\ "," ");

             // If it end in ;@, that's some crazy dd/mm vs mm/dd
             //  switching stuff, which we can ignore
             fs = fs.replaceAll(";@", "");

             // The code above was reworked as suggested in bug 48425:
             // simple loop is more efficient than consecutive regexp replacements.
        }*/
        StringBuilder sb = new StringBuilder(fs.length());
        for (int i = 0; i < fs.length(); i++) {
            char c = fs.charAt(i);
            if (i < fs.length() - 1) {
                char nc = fs.charAt(i + 1);
                if (c == '\\') {
                    switch (nc) {
                        case '-':
                        case ',':
                        case '.':
                        case ' ':
                        case '\\':
                            // skip current '\' and continue to the next char
                            continue;
                    }
                } else if (c == ';' && nc == '@') {
                    i++;
                    // skip ";@" duplets
                    continue;
                }
            }
            sb.append(c);
        }
        fs = sb.toString();

        // short-circuit if it indicates elapsed time: [h], [m] or [s]
        if(date_ptrn4.matcher(fs).matches()){
            cache(formatString, formatIndex, true);
            return true;
        }

        fs = date_ptrn3.matcher(fs).replaceAll("");
        // If it starts with [$-...], then could be a date, but
        //  who knows what that starting bit is all about
        fs = date_ptrn1.matcher(fs).replaceAll("");
        // If it starts with something like [Black] or [Yellow],
        //  then it could be a date
        fs = date_ptrn2.matcher(fs).replaceAll("");
        
        // You're allowed something like dd/mm/yy;[red]dd/mm/yy
        //  which would place dates before 1900/1904 in red
        // For now, only consider the first one
        if(fs.indexOf(';') > 0 && fs.indexOf(';') < fs.length()-1) {
           fs = fs.substring(0, fs.indexOf(';'));
        }

        // Ensure it has some date letters in it
        // (Avoids false positives on the rest of pattern 3)
        if (! date_ptrn3a.matcher(fs).find()) {
           return false;
        }
        
        //去除中文字符 年 月 日 时分秒 等
        fs = date_chinese.matcher(fs).replaceAll("");
        // If we get here, check it's only made up, in any case, of:
        //  y m d h s - \ / , . : [ ] T
        // optionally followed by AM/PM

        boolean result = date_ptrn3b.matcher(fs).matches();
        cache(formatString, formatIndex, result);
        return result;
    }

    /**
     * Given a format ID this will check whether the format represents
     *  an internal excel date format or not.
     * @see #isADateFormat(int, java.lang.String)
     */
    public static boolean isInternalDateFormat(int format) {
            switch(format) {
                // Internal Date Formats as described on page 427 in
                // Microsoft Excel Dev's Kit...
                case 0x0e:
                case 0x0f:
                case 0x10:
                case 0x11:
                case 0x12:
                case 0x13:
                case 0x14:
                case 0x15:
                case 0x16:
                case 0x2d:
                case 0x2e:
                case 0x2f:
                    return true;
            }
       return false;
    }

    /**
     *  Check if a cell contains a date
     *  Since dates are stored internally in Excel as double values
     *  we infer it is a date if it is formatted as such.
     *  @see #isADateFormat(int, String)
     *  @see #isInternalDateFormat(int)
     */
    public static boolean isCellDateFormatted(Cell cell) {
        if (cell == null) return false;
        boolean bDate = false;

        double d = cell.getNumericCellValue();
        if ( ExcelDateUtil.isValidExcelDate(d) ) {
            CellStyle style = cell.getCellStyle();
            if(style==null) return false;
            int i = style.getDataFormat();
            String f = style.getDataFormatString();
            bDate = isADateFormat(i, f);
        }
        return bDate;
    }
    /**
     *  Check if a cell contains a date, checking only for internal
     *   excel date formats.
     *  As Excel stores a great many of its dates in "non-internal"
     *   date formats, you will not normally want to use this method.
     *  @see #isADateFormat(int,String)
     *  @see #isInternalDateFormat(int)
     */
    public static boolean isCellInternalDateFormatted(Cell cell) {
        if (cell == null) return false;
        boolean bDate = false;

        double d = cell.getNumericCellValue();
        if ( ExcelDateUtil.isValidExcelDate(d) ) {
            CellStyle style = cell.getCellStyle();
            int i = style.getDataFormat();
            bDate = isInternalDateFormat(i);
        }
        return bDate;
    }


    /**
     * Given a double, checks if it is a valid Excel date.
     *
     * @return true if valid
     * @param  value the double value
     */

    public static boolean isValidExcelDate(double value)
    {
        return (value > -Double.MIN_VALUE);
    }

    /**
     * Given a Calendar, return the number of days since 1900/12/31.
     *
     * @return days number of days since 1900/12/31
     * @param  cal the Calendar
     * @exception IllegalArgumentException if date is invalid
     */
    protected static int absoluteDay(Calendar cal, boolean use1904windowing)
    {
        return cal.get(Calendar.DAY_OF_YEAR)
               + daysInPriorYears(cal.get(Calendar.YEAR), use1904windowing);
    }

    /**
     * Return the number of days in prior years since 1900
     *
     * @return    days  number of days in years prior to yr.
     * @param     yr    a year (1900 < yr < 4000)
     * @param use1904windowing
     * @exception IllegalArgumentException if year is outside of range.
     */

    private static int daysInPriorYears(int yr, boolean use1904windowing)
    {
        if ((!use1904windowing && yr < 1900) || (use1904windowing && yr < 1904)) {
            throw new IllegalArgumentException("'year' must be 1900 or greater");
        }

        int yr1  = yr - 1;
        int leapDays =   yr1 / 4   // plus julian leap days in prior years
                       - yr1 / 100 // minus prior century years
                       + yr1 / 400 // plus years divisible by 400
                       - 460;      // leap days in previous 1900 years

        return 365 * (yr - (use1904windowing ? 1904 : 1900)) + leapDays;
    }

    // set HH:MM:SS fields of cal to 00:00:00:000
    private static Calendar dayStart(final Calendar cal)
    {
        cal.get(Calendar
            .HOUR_OF_DAY);   // force recalculation of internal fields
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.MINUTE, 0);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        cal.get(Calendar
            .HOUR_OF_DAY);   // force recalculation of internal fields
        return cal;
    }


    @SuppressWarnings("serial")
    private static final class FormatException extends Exception {
        public FormatException(String msg) {
            super(msg);
        }
    }

    /**
     * Converts a string of format "HH:MM" or "HH:MM:SS" to its (Excel) numeric equivalent
     *
     * @return a double between 0 and 1 representing the fraction of the day
     */
    public static double convertTime(String timeStr) {
        try {
            return convertTimeInternal(timeStr);
        } catch (FormatException e) {
            String msg = "Bad time format '" + timeStr
                + "' expected 'HH:MM' or 'HH:MM:SS' - " + e.getMessage();
            throw new IllegalArgumentException(msg);
        }
    }
    private static double convertTimeInternal(String timeStr) throws FormatException {
        int len = timeStr.length();
        if (len < 4 || len > 8) {
            throw new FormatException("Bad length");
        }
        String[] parts = TIME_SEPARATOR_PATTERN.split(timeStr);

        String secStr;
        switch (parts.length) {
            case 2: secStr = "00"; break;
            case 3: secStr = parts[2]; break;
            default:
                throw new FormatException("Expected 2 or 3 fields but got (" + parts.length + ")");
        }
        String hourStr = parts[0];
        String minStr = parts[1];
        int hours = parseInt(hourStr, "hour", HOURS_PER_DAY);
        int minutes = parseInt(minStr, "minute", MINUTES_PER_HOUR);
        int seconds = parseInt(secStr, "second", SECONDS_PER_MINUTE);

        double totalSeconds = seconds + (minutes + (hours) * 60) * 60;
        return totalSeconds / (SECONDS_PER_DAY);
    }
    /**
     * Converts a string of format "YYYY/MM/DD" to its (Excel) numeric equivalent
     *
     * @return a double representing the (integer) number of days since the start of the Excel epoch
     */
    public static Date parseYYYYMMDDDate(String dateStr) {
        try {
            return parseYYYYMMDDDateInternal(dateStr);
        } catch (FormatException e) {
            String msg = "Bad time format " + dateStr
                + " expected 'YYYY/MM/DD' - " + e.getMessage();
            throw new IllegalArgumentException(msg);
        }
    }
    private static Date parseYYYYMMDDDateInternal(String timeStr) throws FormatException {
        if(timeStr.length() != 10) {
            throw new FormatException("Bad length");
        }

        String yearStr = timeStr.substring(0, 4);
        String monthStr = timeStr.substring(5, 7);
        String dayStr = timeStr.substring(8, 10);
        int year = parseInt(yearStr, "year", Short.MIN_VALUE, Short.MAX_VALUE);
        int month = parseInt(monthStr, "month", 1, 12);
        int day = parseInt(dayStr, "day", 1, 31);

        Calendar cal = LocaleUtil.getLocaleCalendar(year, month-1, day);
        return cal.getTime();
    }
    private static int parseInt(String strVal, String fieldName, int rangeMax) throws FormatException {
        return parseInt(strVal, fieldName, 0, rangeMax-1);
    }

    private static int parseInt(String strVal, String fieldName, int lowerLimit, int upperLimit) throws FormatException {
        int result;
        try {
            result = Integer.parseInt(strVal);
        } catch (NumberFormatException e) {
            throw new FormatException("Bad int format '" + strVal + "' for " + fieldName + " field");
        }
        if (result < lowerLimit || result > upperLimit) {
            throw new FormatException(fieldName + " value (" + result
                    + ") is outside the allowable range(0.." + upperLimit + ")");
        }
        return result;
    }

}
